Anterior Interosseous Nerve - Podcast Version 0:00 / 0:00 1x 0.25x 0.5x 0.75x 1x 1.25x 1.5x 1.75x 2x The anterior interosseous nerve is a motor branch of the median nerve. It supplies the deep muscles of the anterior forearm – flexor pollicis longus, lateral half of flexor digitorum profundus and pronator quadratus. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Course The anterior interosseous nerve arises from the median nerve in the proximal forearm, between the heads of the pronator teres. It descends down the forearm, between the flexor pollicis longus and the flexor digitorum profundus. It is accompanied by the anterior interosseous artery. At the level of the wrist, the anterior interosseous nerve passes deep to the pronator quadratus and terminates as small sensory branches. By TeachMeSeries Ltd (2026) Fig 1Course of the anterior interosseous nerve, a branch of the median nerve. Pro Feature - Dissection Atlas Prosection of the deep compartment of the anterior forearm, with the superficial muscles divided and reflected. Prosection of the deep compartment of the anterior forearm, with the superficial muscles divided and reflected. You've Discovered a Pro Feature Access our Dissection Image Library Enhance your understanding with high-resolution dissection images showcasing real-life anatomy. Learn More Sensory Functions The anterior interosseous nerve terminates as articular branches that contribute to sensation at the distal radioulnar, radiocarpal, and intercarpal joints. Motor Functions The anterior interosseous nerve supplies motor innervation the deep compartment of the anterior forearm: Flexor pollicis longus Lateral half of flexor digitorum profundus (index and middle fingers) Pronator quadratus By TeachMeSeries Ltd (2026) Fig 2Deep flexor muscles of the anterior forearm. Frequent questions What is the anterior interosseous nerve? The anterior interosseous nerve is a motor branch of the median nerve that innervates the deep muscles of the anterior forearm, specifically the flexor pollicis longus, lateral half of the flexor digitorum profundus, and pronator quadratus. What muscles are innervated by the anterior interosseous nerve? The anterior interosseous nerve supplies motor innervation to the flexor pollicis longus, the lateral half of the flexor digitorum profundus, and the pronator quadratus, which are crucial for finger flexion and forearm pronation. Where does the anterior interosseous nerve originate? The anterior interosseous nerve arises from the median nerve in the proximal forearm, located between the heads of the pronator teres, and it descends along the forearm. What is the sensory function of the anterior interosseous nerve? While primarily a motor nerve, the anterior interosseous nerve terminates as small sensory branches that provide sensation to the distal radioulnar, radiocarpal, and intercarpal joints. How does the anterior interosseous nerve course through the forearm? The anterior interosseous nerve travels down the forearm between the flexor pollicis longus and flexor digitorum profundus, passing deep to the pronator quadratus before it terminates. Rate This Article